Amazon is making progress getting the major college textbook publishers on board with its Kindle electronic reader. Today, McGraw-Hill Education said it will begin offering 100 higher education titles on the Kindle. McGraw-Hill joins the other major textbook publishers, Cengage Learning, Pearson, and Wiley, which are already selling Kindle editions. Amazon is positioning its new large-screen Kindle DX reader as a replacement for physical textbooks -- and needs to get as many titles as possible into electronic form.

When Amazon announced the Kindle DX in May, it said Cengage Learning, Pearson, and Wiley were all part of the project, but McGraw-Hill's name was conspicuously absent. Now, with McGraw-Hill in the lineup, the Kindle DX can offer titles from the four biggest textbook publishers. According to Subtext, a monthly newsletter covering the book publishing industry, the top four college publishers by 2008 annual sales were Cengage ($1.7 billion), Pearson ($1.6 billion), McGraw-Hill ($610 million), and Wiley ($230 million).

McGraw-Hill said the textbook titles will be used in on-campus pilot programs with the Kindle DX this fall. Amazon and a handful of universities (including the University of Washington) are providing Kindle DXs to some students to test as a textbook replacement.

"The modern student body increasingly requires digital access and capabilities, and we are pleased to be strengthening our partnership with Amazon to help meet these critical needs," said Ed Stanford, president of McGraw-Hill Higher Education, in a statement.

Will students take to the Kindle DX? The devices would be certainly easier to lug around than a pile of books. Students spend a lot of money on textbooks today, though the Kindle DX, currently priced at $489, isn't cheap either.

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